Rotary nosing-in furnace



Aug. 8, 1944. B. G. HARMoN ROTARY NOSING-IN FURNAGE s sheets-Sheet 1 Filed Oct. 24, 1942 .MMWR

A118- 8, 1944 B. G. HARMoN ROTARY NOSING-IN FURNAGE :s sheets-sheet 2 Filed Oct. 24, 1942 ATTORNEYS.

Aug. 8, 1944.

B. G. HARMoN 2,355,527 ROTARY NOSING-IN FURNACE Filed' Oct. 24, 1942 3 Sheets-Sheet 3 55 f I" z 44" 5 [I 3] 40 45 yl 43. l/A/l//s'A/TOAa 6. HAR/WON ArroQ/vys. A

Patented Aug. 8, 1944 ROTARY NOSING-IN FURNACE,

Benjamin G. Harmon, Evanston, Ill., assignor to The Gas Machinery Company, Cleveland, Ohio, a corporation of Ohio Application Octoberl 24, 1942, Serial No. 463,238

7 Claims.

The instant invention relates to heating metal parts, and particularly to improvements in apparatus for heating stock, such as billets, shells, bombs, and solid shot. The invention also includes improved methods of heat-treating cylindrical metal stock. The invention is herein particularly described, and illustrated in the accompanying drawings, as related to its embodiment in and manner of working in improved rotary nosing-in furnaces for heating a certain type of stock, viz., shells for aerial bombs.

The claims of the instant application are limited to the improvements in heating furnaces.

The purposes of the invention are to provide continuous, rotary, end-heating furnaces having great productive capacity, and which can be economically and conveniently utilized, both as regards the efficiency of the furnace operation and the handling of the stock; as also, furnaces in which the stock will be most uniformly heated and which will adequately protect portions thereof not intended to be heated from any adverse effects ldue to the heating operation being performed at that time upon other portions thereof.

The invention is related in many of its aspects to an invention shown in my pending application for U. S. Letters Patent, Serial No. 463,237, entitled Apparatus for, and methods of, heating metal parts, and embodies certain improvements in various features of the invention of said copending application.

The annexed drawings and the following description set forth in detail a form of furnace in which the principle of the invention is embodied, and certain steps by which the improved methods may be worked, such form of furnace constituting, however, only one of various forms in which the principle of the invention may be embodied, and such steps being illustrative only, of the invention embodied in the improved methods.

In said annexed drawings: l

Figure 1 is a vertical section of the improved rotary nosing-in furnace for heating aerial bombs, the lower left-hand portion of the figure being taken in the plane indicated by the lower section line I I, Figure 4, and the remainder of the figure being taken in the plane indicated by the upper section line I I Figure 4;

Figure 2 is an enlarged view of a portion of the right-hand side of Figure 1;

Figure 3 is a vertical section, taken in the planes indicated by the line 3 3, Figure 2;

Figure 4 is a top plan view of the improved furnace;

Figure 5 is a fragmentary vertical section, taken in the planes indicated by the line 5 5, FigureY 4; and

Figure 6 is a plan section, upon an enlarged scale, of which the upper portion is taken in the plane indicated by the lower section line 6 6, Figure 1 and the lower portion is taken in the plane indicated by the upper section line 6 6, Figure 1.

Referring to the annexed drawings in which the same respective parts are indicated by the same several numbers in the different views, an insulated furnace casing includes the insulated refractory base I, an annular insulated side-wall 2, and an arched refractory dome 3, the whole forming a closed furnace casing circular in crosssection and having a heating chamber 4. This chamber 4 is fired by burners 5 to which are fed combustion air through the piping 6 and oil through the piping 8. Piping I serves to furnish atomizing air. The combustion air is furnished 'to the piping S through a motor-blower system 9, Figures 4 and 5. Vertical passages II in the side-wall 2 serve as iiues for the escape of waste products of combustion from the heating chamber 4, the passages I I communicating with the heating chamber 4 through an annular base liue II1 formed in the wall 2. The waste products escape from the center of the heating chamber 4 into the annular flue II1 through opening II2 in the side wall 2, and from the bottom of the heating chamber through ports II3 which communicate by means of vertical passages H4 with the annular passage H1.

The furnace is supported by a structural base I0 mounted upon'a door I2. The actual support for the furnace upon the base I0 is through an annular track I4 rested on the base I0 and engaged by rollers `I3 dependently supported in Ibrackets 2t secured to overlying I-beams I9` which in turn are secured to the bottom of the refractory base I. There is thus provided a rotatable movement for the furnace upon the annular track I4, the prime mover being a variable ,f speed motor I5 whose shaft through intermediate gearing IE and gear reducers drives a gear I'I through the furnace side-wall 2 so that the shell end being heated constantly extends further into the furnace, as illustrated in Figures 4 and 6, assuming the direction of furnace rotation is as indicated by the arrows. A loading and unloading zone 2| is suggested in Figures 4 and 6, and, therefore, a shell which it is assumed has just been mounted in the furnaceb wall for rotation therewith and heating is indicated by 251, Figures 4 and 6, and a shell which has been rotated with the furnace and received its heating treatment and is ready for withdrawal is indicated by 2 52. The shells 25 intermediate the unheated shell 251 and the heated shell 252 extend progressively further inwardly of the heating chamber 4, as clearly indicated in Figures 4 and 6. By such a heating procedure, the shells 25 are fed progressively toward the concentration of heat. Also, the heating effect longitudinally of the axis of the shell 25 varies downwardly from a maximum at the end of the shell 25 extended into the heating chamber 4 toward the oppoiste end of the shell, thus to provide the desired heating effect forthe nosing-in operation.

The shells 25 .are mounted in an annular series of chambered steel wall blocks 26 forming part of the furnace sidewall, these blocks 26 having cylindrical openings with their axes radial relative to the furnace, the openings forming journal surfaces for'rotatable shell housings 28 within which the shells are mounted and are rotatable with the housings 28 by reason of a frictional contact therewith. The chambers 21 of the steel blocks 26 serve as water reservoirs for a purpose hereinafter fully explained. The shell housings 28 are formed at their inner ends with internal flanges 281 and with longitudinal inwardly extending ribs 283 by which they engage and support the inner ends of the shells 25 and with external flanges 282 intermediate their ends which determine the extent to which the housings 28 can move inwardly toward the heating chamber `4.

The inner portion of that part of the furnace wall, of which the outer portion is comprised of the steel blocks 26, is formed of refractory blocks 3| having openings 3|1 through which the shells 25 extends, which openings 3|1 are enlarged and thus extend the effective heating zone and prevent the spalling of the blocks 3| which would result from heat if the blocks 3| had direct contact with the shells 25. Also, the outer ends of the' shells 25 contained within the shell housings 28 are protected by being water-jacketed by the water chambers 21 to the lower portion of which water is fed through a pipe 30, the water escaping from the tcp of the chambers 21 and being conducted by means (not lshown) to a waste water trough 32, Figure 1, mounted on the structural base ID.` In order that the water pipe 36 may rotate with vthe furnace, it is connected to a feed line 33 by a coupling 34 in which its inner end is rotatably mounted.

The shellY housings 28 are formed with out wardly ared terminal flanges 29 which are formed into a circular series of teeth 291 which, as the furnace is rotated,are engaged by a circular series of pins 39 welded to and inwardlyextended from a circular angle 40 secured to brackets which are supported by and extended inwardly from a series of upright standards 38 mounted on the structural furnace base member IU. It is evident, then, that the rotation of the furnace induces the rotation of the shell holders 28 and that the shells 25 which are rested upon .outer ends of the shells 25 rest.

the flanges 281 and ribs 283 of the shell holders 28 will tend also to rotate by frictional contact. The outer portions of the shells 25 extending outwardly from the furnace are also so mounted as to permit the rotation or rolling thereof. The effect is to rotate the shells 25 by a rolling action. The mounting of the outer ends of the shells 25 will now be described.

Depending from brackets 31 secured to and extended outwardly from the furnace side-wall 2 are shell supports 36, these supports being provided in pairs, an opposed pair for each shell 25 to be supported, Figure 3, and having lower end inwardly-inclined angular portions 361 to which are secured ball transfers 35 upon which the The securing of the pairs of supports 36 to the hangers 31 is effected by means of two series of circumferentially elongated slots 52 formed in the brackets 31 and engaged by bolts 53, Figures 3 and 6. Furthermore, an .additional radially-aligned pair of series of circumferentially elongated slots is formed in the brackets 31, Figure 6. Thus ad justment is afforded whereby the pairs of supports 36 can be suspended at varying distances from each other and also can be suspended at varying distances from the furnace interior to accommodate shells 25 both of different diameters and also of different lengths.

The rotation of the shells 25 during heating on the flanges 281, ribs 283, and the ball transfers 35 insures uniform heating and prevents distortion of the shells by sagging.

As hereinbefore stated, by reference to a sug gestionY thereof in Figures 4 and 6, the shells 25 are progressively and automatically fed further into the furnace interior as they rotate with the furnace from a loading thereof in the zone 2| to a return to said zone 2| for their unloading.

-. This progressive inward feeding of the shells 25 is effected by the mechanism now to be described.

Upon a circular series of platforms 4| extended outwardly from the standards 38 are mounted short angle standards 42 formed with bases 43.

. To the top of the standards 42 is secured a leg of a 'z the same horizontal plane as the axis of the shells 25. The base 43 is secured to and adjustable inwardly of the platform 4| by bolt 45, the bolt 45 engaging an oblique elongated slot 44 formed in the platform 4|. It will be noted in Figures 4 and 6 that the tops of the several platforms 4|, reading clockwise from the working zone 2|, are increasingly exposed and this for the reason that the short standards 42 reading clockwise are progressively adjusted further inwardly of the furnaceffsuch structure is for the purpose of progressively biasing inwardly of the furnace the angle 421 and the metal strip 5D which surrounds the furnace except for the region of the loading and unloading Zone 2|, the metal strip 5l) being positioned to engage the outer ends of the shells 25, whereby the strip 50 functions as a cam and progressively pushes the shells 25 further inwardly of the furnace as the shells 25 rotate with the furnace with their outer ends engaged by the cam 50. The progressive intersection of the furnace interior by the ends of the shells 25 being heated is indicated in Figures 4 and 6.

Certain important ladvantages attach to the loose mounting of the shells in rotating sleeves,

.thus causing the shells to rotate by surface con-` tact only with the sleeves. When the sleeves and shells are fixedly locked together, extra labor is necessary for clamping and unclamping the sleeves and shells. Furthermore, the shells, when loosely positioned in the sleeves, can easily be withdrawn from the furnace at any point around the furnace periphery. This latter advantage is particularly important in the event of power failure because, in that event, the shells, as Well as the furnace, will sto-p rotating, but, inasmuch as there is no need `of unclamping the shells in the structure herein shown and described, the removal thereof from the outside of the furnace at any point around the furnace periphery can be quickly effected.-V

The supporting of the rotatable sleeves in which the shells are loosely mounted by blocks which also serve as Water-cooled jackets provides a sharp heat cut-off between the part of the shell which is being heated and the part which is not being heated and thus the desired varied workbeing formed with means effecting the rolling of Acylindrical stock mounted in the holders as the latter rotate, and automatic means for progreshsively feeding stock through the holders into the furnace.

4. A heating furnace comprising a structure having a base, a side-wall, and a dome, a series of stock-holders rotatably mounted in thek side- QWalI, means for rotating the holders, and cam member surrounding the side-wall in alignment with the stock-holders and progressively biased able characteristics of the different parts of the v shell are effectively controlled.

What I claim is:

l. A heating furnace comprising a structure having a base, a side-Wall, and a dome, a series of stock-holders rotatably mounted in the sidewall, means for jrotating the holders, and automatic means for progressively feeding stock through the holders into the furnace.

2. A heating furnace comprising a structure having a base, a side-wall, and a dome, a series of stock-holders rotatably mounted in the side- Wall, means forV rotating the holders, the latter Ybeing formed with means effecting the rotating of cylindrical stock mounted in the holders as the latter rotate, and automatic means for progressively feeding stock through the holders into the furnace.

3. A heating `furnace comprising a structure having a base, a side-wall, and a dome, a series of stock-holders rotatably mounted in the side- Wall, means for rotating the holders, the latter toward the side-wall.

6. Stock-supporting means for heating furnaces comprising a furnace side-wall, a chambered and open-ended stock-receiving member forming part of the side-Wall, a stock-support secured to the side-wall and extended eXteriorly thereof in alignment with the stock-receiving member, and means for adjusting the extension of said stock-support to vary the distance vthereof from the side-wall.

7. Stock-supporting means for heating furnaces comprising a furnace side-wall, a cham- Y bered and open-ended stock-receiving member forming part of the side-Wall, a stock-support secured to the side-wall and extendedv exteriorly thereof in alignment with the stock-receiving member, said extension being formed to permit sliding of stock therethrough, means for adjusting the extension of said stock-supportl to vary the distance thereof from the side-Wall, and cam means for progressively feeding stockY on the stock-support and through the stock-receiving member into the furnace.

BENJAMIN G. HARMON. 

